import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;

@WebServlet("/index")
public class IndexServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // 返回一个主页, (简单的html片段)

        // 此处需要得到用户名, 在登录页面中已经存储进去了, 这里会话一定是存在的
        HttpSession httpSession = req.getSession(false);
        // HttpSession 里的 value 是 Object, 需要强转
        // 用户名
        String username = (String) httpSession.getAttribute("username");
        // 登录次数
        int count = (int) httpSession.getAttribute("count");
        count += 1;
        httpSession.setAttribute("count", count);
        resp.setContentType("text/html; charset=utf8");
        resp.getWriter().write("<h3>欢迎你! " + username + ", 这是第 " + count + " 次访问主页</h3>");
    }
}
